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Discussion Starter #1
This will be a bit of book but i want to express the issue and what i have done in writing. Maybe someone can narrow it down.

First off, 1988 350 tbi fully rebuilt kept it stock other than .030 over on the bore.

Trouble starting after it sits for awhile do to not getting fuel right away. Once it does it fires no problem and idles very nice in park and neutral. In gear it bogs slightly and feels like i put a bigger cam in it. Little rough. If you hit the gas hard it seems to be fine. But under a normal driving condition at low and slow acceleration, it bogs down sputters, wants to die and a slight knocking occurs. Like its getting choked out. This happens in park and in gear. Worse when in gear. The knocking i think is pinging from a wrong mix of air and gas.

I should note that it was doing this before I rebuilt it as well, part of the reason i did it in the first place.

Ultimately i would diagnose it as running lean? Certainly not rich, i dont smell gas fumes at all.

Now let me explain what i have done and replaced thus far.

Fully rebuilt block,heads,and tbi. Machine shop did the heads in full and cleaned up the block. I did all the assembly afterwards, clearances of everything seem to check out for the most part.
Since this seems more like a fuel issue ill try to focus on that stuff.

So, fully cleaned and rebuilt the tbi,
New parts as follows, injectors, regulator, spring, iac, tps, egr, fuel filter, fuel pump and sender, icm, new plugs, coil, wires, new map sensor, new thermostat, new water pump, belt, new knock sensor.

Reused parts but kind of newish. Esc, egr solenoid, distributor/dizzygear. Cleaned cap/rotor.

Deleted the air pump and lines, plugged off the exhaust manifolds. Deleted the cat.

Old parts reused, o2 sensor, coolant temp sensor, oil temp/pressure sensor, alternator, Original ECM. All Vacuum lines.

Probably leaving some things out idk. Timing is set correct at initial zero according specifications on fan shroud.

I did find today that by unplugging the egr vacuum line, the idle speed increased and throttle response felt better but still far from perfect and it was still pinging (hopefully not a rod bearing, i would cry). I should check to see if the egr solenoid is getting power some how. Maybe theres a computer fault there.

My other thoughts on what should be next to try. Make sure fuel return and vacuum lines aren’t clogged. Maybe a new fuel relay and oil pressure switch. That could be the slow starting issue I suppose but could be the ecm as well though. I actually might start by inspecting the ecm to see if it smells/looks burnt out at all.

I know its a lot to read but id really like help to narrow it down before i throw more money at it.

Thanks.
 

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Check fuel pressure first, then make sure your EGR valve isn't leaking. TBI's had issues with them and/or the egr solenoid holding the valve open. Another common problem was the pickup coil inside the distributor. My 90 had this drivability issue and it was the pickup coil. ran like new once replaced.
 

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Discussion Starter #3
So, i got it to run much better after playing with the iac and reseting it/idle adjustments and playing with the timing. I also replaced the fuel relay which is definitely helping it to start faster. Now i still had an intermittent knock sound. i said wtf and pulled the valve cover off. Number 7 intake was stationary. No movement. I touched it and it began to move but knocked, so it was supper loose. Took me a few days after to realize that the rocker stud which is press fit lifted up and worked its way loose. It might have been that way from the start i really don’t remember. So i guess thats a good thing though meaning there shouldn’t be any damage, the lifter looks practically untouched. Like to assume that the cam is probably okay as well.

Now what should i do about the studs...???? Cast iron original heads btw.

And whats people opinions on melling cams and lifters (quality wize)? That is what i have in there right now.
 
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